1. Field of the Invention
This invention relates generally to brewers designed to produce single beverage servings by injecting heated liquid into disposable filter cartridges containing a dry beverage medium, and is concerned in particular with an improved beverage filter cartridge holder for such brewers.
2. Description of the Prior Art
A known disposable beverage filter cartridge is disclosed in U.S. Pat. No. 5,840,189 (Sylvan et al.) The cartridge includes a piercable cup-shaped base internally subdivided by a permeable filter into first and second chambers. A dry beverage medium is contained in the first chamber, and the cup-shaped base is closed by a piercable lid.
In use, the lid and base are pierced, respectively by inlet and outlet probes acting in opposite directions. The inlet probe serves to admit heated liquid into the first chamber where it infuses with the beverage medium to produce a beverage. The beverage passes through the filter into the second chamber, from which it exits via the outlet probe.
This known beverage filter cartridge has gained rapid and increasingly widespread acceptance, notwithstanding certain problems and disadvantages relating to its use that have persisted since its initial introduction.
For example, as compared to the lid, the bottom of the cup-shaped base is relatively thick, with a higher resistance to piercing. The bottom cannot easily be thinned without adversely affecting the required thickness of the cup""s sidewall to prevent permeability to oxygen and the ability to connect the filter material to the sidewall without damaging the oxygen barrier material. Thus, in the course of being punctured by the outlet probe, the bottom exhibits a tendency to distort inwardly, with an accompanying buckling of the container sidewall. Bottom distortion accompanied by sidewall bucking can adversely affect the puncturing process, resulting in leakage around the outlet probe.
A related problem stems from the need to equip the brewers with expensive metallic outlet probes that can be sharpened to the extent necessary to effect piercing of the more resistant container bottoms, and that can resist wear over prolonged periods of use.
As disclosed in the above referenced patent application, these problems have been addressed by redesigning and rearranging the cartridge components, resulting in the first and second chambers being accessible, respectively, by inlet and outlet probes acting on one side of the cartridges to pierce only the lid.
The present invention has as its principal objective the provision of a modified beverage filter cartridge holder incorporating inlet and outlet probes arranged to access the first and second chambers of the redesigned cartridge by piercing only the cartridge lid.
This and other objectives, features and advantages of the present invention will now be described in greater detail with reference to the accompanying drawings, wherein: